Effect of Pretreatments on Seed Germination of <i>Acacia Species</i>

Abstract

This study was conducted to investigate the effects of boiling water, sulfuric acid, and KOH as a pretreatment to improve the germination of two Acacia species, Acacia floribunda and Acacia retinodes. In the case of boiling water, the seeds were immersed at 80°C and 100°C for 30 minutes and 60 minutes, respectively. For sulfuric a cid, t he s eeds w ere immersed a t 50% a nd 98% concentrations for 10, 20, and 40 minutes, respectively. For KOH, the seeds were immersed in 15%, 20%, and 25% concentrations for 10, 20, and 30 minutes, respectively. Seed germination characteristics such as germination percentage, germination energy, germination rate, mean daily germination, and mean germination time were investigated. For A. floribunda, the boiling water showed higher germination percentages than the control (16.0%), with the highest germination percentage observed for 84.0% at 100°C for 5 minutes. This resulted in good germination energy, germination rate, and mean daily germination, but mean germination time was lower than the control. When exposed to sulfuric acid, the control showed a germination percentage of 30.0%, with the highest germination percentage measured at 76.0% in 98%sulfuric acid for 40 minutes. In the case of A. retinodes, boiling water at 80°C for 30 minutes showed the highest germination percentage of 68.0%, compared to the control (20.0%). The germination energy, germination rate, mean daily germination, and mean germination time were also better than the control. The highest germination percentage was 49.3% when exposed to a 98% sulfuric acid solution for 40 minutes. The germination percentages when exposed to KOH were found to be 36% in a 15% KOH solution for 10 minutes in A. floribunda, and 34.6% in A. retinodes in a 15% KOH solution and in a 25% KOH solution for 10 minutes, respectively, but there was no effect compared to the control. The results of this study suggest that boiling water pretreatments are the most suitable for enhancing the germination percentage of A. floribunda and A. retinodes.